Are you joking? Bladedancers are already easy enough to kill. Removing their defense boost will not only make them useless in Crucible but it will also destroy any hopes they ever had at becoming good in PvE. It is stupidly easy enough to kill bladedancers as it is, all it takes me is a well placed fusion/magnet grenade and several shots of a good weapon. I have even killed Bladedancers with nothing more than a few Invective shots followed by a melee. Not to mention the damage done by a good burst of a fusion rifle. Supers are meant to be good, and the Bladedancer is terrible anywhere other than Crucible. Let it be.